Is a man allowed to masturbate to treat premature ejaculation if a doctor has recommended such a behavioural technique to overcome this problem permanently?
Bismihi ta'ala
Masturbation is haram, and the aforementioned situation would not exempt a man from conducting such an act.
He can either request assistance from his wife, if he is married, and if not, to find alternative halal methods, which he certainly will be able to find.
With prayers for your success.